package yxm.zyf.love.utils;

public class TestSB {

    public static void main(String[] args) {
        String a="";
        long currentTimeMillis = System.currentTimeMillis();
        for (int i = 0; i < 10000; i++) {
            a=i+""+a;
        }
        System.out.println(currentTimeMillis-System.currentTimeMillis());
        currentTimeMillis = System.currentTimeMillis();
        StringBuilder sb=new StringBuilder();
        for (int i = 0; i < 10000; i++) {
            sb.append(i+"");
        }
        String string = sb.toString();
        System.out.println(currentTimeMillis-System.currentTimeMillis());
    }
}
